Evaluation of Graphene as a Novel Bioactive Stent Coating: Comparative Performance and Vascular Response in Porcine Coronary Arteries

Coronary drug-eluting stents (DESs) are the current clinical standard, yet delayed endothelialization remains a critical challenge. Graphene-based coatings have emerged as promising cardiovascular biomaterials due to their favorable hemocompatibility and ability to support endothelial cell growth. In this study, we evaluated the in vivo performance of graphene-coated stents (GCSs) compared with commercial sirolimus-eluting stents in a Polish White swine model (n = 10). Stents were implanted into major coronary branches, with follow-up at 30 and 90 days using quantitative coronary angiography (QCA), optical coherence tomography (OCT), and cryogenic scanning electron microscopy (cryo-SEM). No systemic toxicity, mortality, thrombotic events, or ischemic complications were observed during the study period. QCA demonstrated no significant differences in percent diameter stenosis between GCSs and DESs at either 30 days (12.3 ± 6.1% vs. 8.6 ± 5.8%, p = 0.2782) or 90 days (18.3 ± 10.5% vs. 9.6 ± 6.6%, p = 0.1074). OCT analysis confirmed comparable lumen and neointimal parameters between groups, while demonstrating a favorable, although non-significant, trend toward a lower percentage of uncovered struts in GCSs. Cryo-SEM imaging demonstrated stable tissue integration and a preserved healing response surrounding GCSs. Collectively, these findings indicate that GCSs are safe and biocompatible and demonstrate mid-term vascular performance comparable to clinically used DES platforms. The presented results support further investigation of graphene-based coatings as potential surface-modification strategies for coronary stents.